Power supply regulation has become much more integrated due to the number of features that are incorporated in general power management circuitry. The power management circuitry that presently is utilized allows designers to incorporate single chip devices to be manufactured that provide a wide range of versatility. When initially defining the features of an integrated circuit power management chip, the designer must consider all possible applications that can be facilitated with their part.
One feature that must be accommodated in designing any type of power management system is the type of regulation that can be accommodated. Typically, there are two types of regulation, switching regulators and linear regulators. The components required for these features are typically external components. For example, a switching regulator requires a switching transistor, a switching diode and some type of reactive component, such as an inductor. These are not adaptable to fabrication in an integrated circuit as the switching transistor requires too much power and the inductor, of course, requires very high "Q", which is not a feature that can be practically designed in an integrated circuit. However, one problem facing a designer is the fact that accommodating two different types of regulations typically requires two separate sets of interface circuits that must be disposed within the integrated circuit. Additionally, each of these features will be associated with separate I/O pins. The primary goal of a designer is to place as much of the functionality onto the integrated circuit as possible without requiring a large number of pins to interface with external components, thus minimizing the number of external components required to those that are virtually impossible to fabricate on an integrated circuit. In the past, this has been difficult when trying to accommodate different types of regulation circuits.